Recent decades have seen a large increase in surface scums (blooms) of cyanophytes (blue-green algae and blue-green bacteria) in inland waters. These are potentially toxic to mammals, including humans, and have caused considerable public concern in Europe, Australasia, and North America. They are often associated with eutrophication, and much has been invested in their control. Not all blooms, ...

Proposition 1.1. Let f : R1 → R2 be a homomorphism of rings. If J is an ideal of R2, then f (J) is an ideal of R1 containing ker(f) and furthermore f(f(J)) ⊆ J . Now let f : R1 → R2 be an epimorphism of rings. If J is an ideal of R2 then f(f (J)) = J . If I is an ideal of R1 then f(I) is an ideal of R2. Furthermore we have I ⊆ f (f(I)) = I + ker(f) and thus I = f(f(I)) if I contains ker(f). Thu...

عاطقلا طبر ي يذ لا ة يبرهكلا ىو قلا ماظنل يكيمانيدلارارقتسلال ةضيفتسم ةيلمع ةسارد ثحبلا اذه مدقي ني ب ة لوقنملا ةرد قلا ةدا يز ى لع ك لذ ريثأ ت و ةيدوعس لا ءا برهآ ةآر ش ن م ط سولأا عا طقلا و يقرش لا نيعاطقلا ، ىوقلا مظن تاتبثم طبض للاخ نم كلذو . دقل شم ةغايص مت ةلك طبض ةروص ىف تاتبثملا هذه ةلثمأ ةلكشم . ماظنلا ءادأ نيسحتل ك لذو ةدر فنملا ماظنلا ميق ىلع نادمتعت فده يتلاد حارتقا مت دقلو . د قلو ...

INTRODUCTION.................................................................................. 431 PROBLEMS IN THE ETIOLOGICAL STUDY OF VIRAL RESPIRATORY ILLNESS IN INFANTS AND CHILDREN 431 CLINICALLY INDISTINGUISHABLE RESPIRATORY ILLNESSES.433 Rhinitis...................................................................................... 433 Tonsillitis or Pharyngitis 43 Exanthematous Disease 4...

436 BRIEF NOTES